The information on a bolt thread-size chart varies depending on its type, but dimensions and thread count are basic data that are always included. The easiest charts for identifying dimensions are layover charts that show full-size outlines and list unique characteristics of each.
Picking an informative chart is important to prevent misidentification. Bolt Depot offers a range of printable layover guides that allow correct identification of bolts and shoulder bolts in both metric and U.S. measurements. A separate thread gauge chart clearly shows the differences in a range of coarse and fine threads, again in both metric and U.S. sizes.